施肥深度对直播麻疯树生长及养分吸收的影响

Effects of Fertilization Depth on Growth and Nutrient Absorption of Direct Seeding Jatropha curcas L.

为确定麻疯树基肥施用适宜深度,采用盆栽试验,研究不同施肥深度（0、10、20、30 cm）对麻疯树云热-1号根、茎及叶生长、养分含量及养分积累量的影响。结果表明：与不施肥比较,施肥可显著促进麻疯树各器官生长,提高各器官氮、磷、钾养分含量和积累量。其中,在试验初期,地径和茎高随施肥深度的增加而减小;之后,地径和茎高以施肥深度20 cm的最大,其次是施肥深度10 cm的。随施肥深度增加,4条侧根总长、1级侧根总数、各器官干物质积累量和氮、磷、钾积累量先增而后减,其中均以施肥深度20 cm的最大,处理间植株干物质积累总量和氮、磷及钾积累总量的差异显著;肥料深施（10-30 cm）也明显提高各器官氮、磷、钾含量。可见,麻疯树基肥施用土层深度以20 cm较适宜。

In order to determine reasonable base fertilizer application depth for direct seeding Jatropha curcas L.,a pot experiment was conducted to investigate the effects of fertilization depth（ 0,10,20,30 cm） on the growth,nutrients content and nutrients accumulation of roots,stem and leaves of Jatropha curcas cultivar Yunre No. 1. The results showed that fertilizer application significantly accelerated the growth and increased content and accumulation of N,P and K in each organ compared with the control without fertilizer. As fertilizer application depth increased,the ground diameter and stem height decreased during the early stages of the experiment. Later,the ground diameter and stem height with fertilization in20 cm depth were optimal,followed by fertilization depth of 10 cm. As fertilizer application depth increased,the primary lateral root total length,lateral root total number,dry matter accumulation and accumulation of N,P and K in each organ increased firstly and then decreased,which reached the peak values when the fertilization depth was 20 cm. There were significant differences in the total dry matter accumulation and total accumulation of N,P and K in plant among four fertilizer application depth treatments. Deep fertilizer application（ 10—30 cm depth） obviously increased the content of N,P and K in roots,stem and leaves. The suitable soil depth of base fertilizer applied was 20 cm.